Jawless fish Lamprey & Hagfish

Hagfish

Hagfish Life History Characteristics Morphology One of the oldest vertebrates still living in deep, marine waters It is a scavenger and predator of worms Burrows in soft substrates (ex: sand, mud) Extant – still living species One nostril surrounded by barbels Barbels – whisker-like organ near the mouth found in some fish No paired fins Cartilaginous skeleton Degenerate eye covered by skin Several gill slits Multiple hearts One heart serves as main pump Other three serve as accessory pumps

Hagfish Live in cold waters around the world, from shallow to as deep as 5,500 feet Can go months without food Can absorb nutrients through skin Sometimes called ‘slime eels’ but are not eels Class Agnatha – meaning jawless fish Have 2 rows of tooth-like structures that they use to burrow into carcasses While eating carrion or live prey, they tie their tails into knots to generate torque and increase force of their bites To ward off predators, hagfish produce slime When harassed, glands lining their bodies secrete stringy protein that, upon contact with seawater, expanding into transparent, sticky substance Hagfish can fill a 5-gallon bucket with the slime in minutes Slime gives hagfish a slippery exit when attacked by predators Hagfish can ”sneeze” out its slime-filled nostril and tie its body into a knot to keep the slime from dripping onto its face Vancouver Aquarium Hagfish Slime

Hagfish Help to clean and recycle dead animals from the seafloor Hagfish feeding on whale 12% of hagfish species are at an evaluated risk of extinction Hagfish are threatened from both intentional fishing and unintentional bycatch Weren’t always fished, but because several more preferable fish species are overfished and hard to catch, fishermen have moved down to catching hagfish Eddie and the Hagfish

Lamprey

Lamprey Life History Characteristics Morphology Freshwater forms spend entire life in this habitat Some forms hatch and grow in freshwater, migrate to ocean to mature and return to freshwater to spawn Spawn – mate; reproduce Long, eel-like, similar to hagfish Internal skeleton of cartilage, complete braincase and rudimentary true vertebrae Round, sucker-like mouth has numerous, tooth-like plates Plates used for grasping prey and then rasping a hole, through which fluids and tissues are sucked

Lamprey Live in coastal and freshwater habitats Found in temperate regions around the world, except Africa Eel-like, scaleless animals range from about 15 – 100 centimeters long Well-developed eyes, one or two dorsal fins, a tail fin, a single nostril on top of head and several gill openings on each side of body Lack bones, jaws and paired fins Skeleton consist of cartilage Mouth is a round sucking aperature containing many teeth Sea Lamprey Breathing Paddlefish Parasites http://www.britannica.com/animal/lamprey

Lamprey Begin lives as burrowing freshwater larvae At this stage, toothless, having simple eyes and feed on microorganisms After several years, they transform into adult and typically move into the sea to begin a parasitic life Attaching to fish by their mouth and feeding on blood and tissues of host To reproduce, lampreys return to freshwater, build a nest, then spawn and die Not all lamprey spend time in the sea Some are landlocked and remain in freshwater When an invasive species, it can have a disastrous impact on valuable fishes Lampreys have long been used to some extent as food; however, they are of no great economic value "Silent Invaders" Sea Lamprey 2013